#include <gtest/gtest.h>

#include "Viewport/ViewportHostRenderTargets.h"

#include <string>

namespace {

using XCEngine::Editor::BuildViewportColorSurface;
using XCEngine::Editor::BuildViewportObjectIdSurface;
using XCEngine::Editor::BuildViewportRenderTargetsReuseQuery;
using XCEngine::Editor::DestroyViewportRenderTargets;
using XCEngine::Editor::EditorViewportKind;
using XCEngine::Editor::ViewportRenderTargets;
using XCEngine::RHI::Format;
using XCEngine::RHI::RHIResourceView;
using XCEngine::RHI::RHITexture;
using XCEngine::RHI::ResourceStates;
using XCEngine::RHI::ResourceViewDimension;
using XCEngine::RHI::ResourceViewType;
using XCEngine::RHI::TextureType;

class DummyTexture final : public RHITexture {
public:
    explicit DummyTexture(Format format = Format::R8G8B8A8_UNorm)
        : m_format(format) {
    }

    uint32_t GetWidth() const override { return 1; }
    uint32_t GetHeight() const override { return 1; }
    uint32_t GetDepth() const override { return 1; }
    uint32_t GetMipLevels() const override { return 1; }
    Format GetFormat() const override { return m_format; }
    TextureType GetTextureType() const override { return TextureType::Texture2D; }
    ResourceStates GetState() const override { return m_state; }
    void SetState(ResourceStates state) override { m_state = state; }
    void* GetNativeHandle() override { return nullptr; }
    const std::string& GetName() const override { return m_name; }
    void SetName(const std::string& name) override { m_name = name; }
    void Shutdown() override { shutdownCalled = true; }

    bool shutdownCalled = false;

private:
    Format m_format = Format::R8G8B8A8_UNorm;
    ResourceStates m_state = ResourceStates::Common;
    std::string m_name;
};

class DummyResourceView final : public RHIResourceView {
public:
    explicit DummyResourceView(
        ResourceViewType viewType = ResourceViewType::RenderTarget,
        Format format = Format::R8G8B8A8_UNorm)
        : m_viewType(viewType)
        , m_format(format) {
    }

    void Shutdown() override { shutdownCalled = true; }
    void* GetNativeHandle() override { return nullptr; }
    bool IsValid() const override { return true; }
    ResourceViewType GetViewType() const override { return m_viewType; }
    ResourceViewDimension GetDimension() const override { return ResourceViewDimension::Texture2D; }
    Format GetFormat() const override { return m_format; }

    bool shutdownCalled = false;

private:
    ResourceViewType m_viewType = ResourceViewType::RenderTarget;
    Format m_format = Format::R8G8B8A8_UNorm;
};

TEST(ViewportRenderTargetsTest, BuildReuseQueryReflectsCurrentResourcePresence) {
    ViewportRenderTargets targets = {};
    targets.width = 1280;
    targets.height = 720;
    targets.colorTexture = reinterpret_cast<RHITexture*>(static_cast<uintptr_t>(0x1));
    targets.colorView = reinterpret_cast<RHIResourceView*>(static_cast<uintptr_t>(0x2));
    targets.depthTexture = reinterpret_cast<RHITexture*>(static_cast<uintptr_t>(0x3));
    targets.depthView = reinterpret_cast<RHIResourceView*>(static_cast<uintptr_t>(0x4));
    targets.objectIdTexture = reinterpret_cast<RHITexture*>(static_cast<uintptr_t>(0x5));
    targets.objectIdView = reinterpret_cast<RHIResourceView*>(static_cast<uintptr_t>(0x6));
    targets.objectIdShaderView = reinterpret_cast<RHIResourceView*>(static_cast<uintptr_t>(0x7));
    targets.textureId = static_cast<ImTextureID>(static_cast<uintptr_t>(0x8));

    const auto query =
        BuildViewportRenderTargetsReuseQuery(EditorViewportKind::Scene, targets, 1280, 720);

    EXPECT_EQ(query.width, 1280u);
    EXPECT_EQ(query.height, 720u);
    EXPECT_TRUE(query.resources.hasColorTexture);
    EXPECT_TRUE(query.resources.hasColorView);
    EXPECT_TRUE(query.resources.hasDepthTexture);
    EXPECT_TRUE(query.resources.hasDepthView);
    EXPECT_TRUE(query.resources.hasObjectIdTexture);
    EXPECT_TRUE(query.resources.hasObjectIdView);
    EXPECT_TRUE(query.resources.hasObjectIdShaderView);
    EXPECT_TRUE(query.resources.hasTextureDescriptor);
}

TEST(ViewportRenderTargetsTest, BuildSurfaceUsesTargetAttachmentsAndStates) {
    DummyResourceView colorView(ResourceViewType::RenderTarget);
    DummyResourceView depthView(ResourceViewType::DepthStencil, Format::D24_UNorm_S8_UInt);
    DummyResourceView objectIdView(ResourceViewType::RenderTarget);

    ViewportRenderTargets targets = {};
    targets.width = 800;
    targets.height = 600;
    targets.colorView = &colorView;
    targets.depthView = &depthView;
    targets.objectIdView = &objectIdView;
    targets.colorState = ResourceStates::Common;
    targets.objectIdState = ResourceStates::PixelShaderResource;

    const auto colorSurface = BuildViewportColorSurface(targets);
    ASSERT_EQ(colorSurface.GetColorAttachments().size(), 1u);
    EXPECT_EQ(colorSurface.GetColorAttachments()[0], &colorView);
    EXPECT_EQ(colorSurface.GetDepthAttachment(), &depthView);
    EXPECT_EQ(colorSurface.GetColorStateBefore(), ResourceStates::Common);

    const auto objectIdSurface = BuildViewportObjectIdSurface(targets);
    ASSERT_EQ(objectIdSurface.GetColorAttachments().size(), 1u);
    EXPECT_EQ(objectIdSurface.GetColorAttachments()[0], &objectIdView);
    EXPECT_EQ(objectIdSurface.GetDepthAttachment(), &depthView);
    EXPECT_EQ(objectIdSurface.GetColorStateBefore(), ResourceStates::PixelShaderResource);
}

TEST(ViewportRenderTargetsTest, DestroyViewportRenderTargetsShutsDownAndClearsState) {
    auto* colorTexture = new DummyTexture();
    auto* colorView = new DummyResourceView(ResourceViewType::RenderTarget);
    auto* depthTexture = new DummyTexture(Format::D24_UNorm_S8_UInt);
    auto* depthView = new DummyResourceView(ResourceViewType::DepthStencil, Format::D24_UNorm_S8_UInt);
    auto* objectIdTexture = new DummyTexture();
    auto* objectIdView = new DummyResourceView(ResourceViewType::RenderTarget);
    auto* objectIdShaderView = new DummyResourceView(ResourceViewType::ShaderResource);

    ViewportRenderTargets targets = {};
    targets.width = 640;
    targets.height = 360;
    targets.colorTexture = colorTexture;
    targets.colorView = colorView;
    targets.depthTexture = depthTexture;
    targets.depthView = depthView;
    targets.objectIdTexture = objectIdTexture;
    targets.objectIdView = objectIdView;
    targets.objectIdShaderView = objectIdShaderView;
    targets.imguiCpuHandle.ptr = 123;
    targets.imguiGpuHandle.ptr = 456;
    targets.textureId = static_cast<ImTextureID>(static_cast<uintptr_t>(789));
    targets.colorState = ResourceStates::RenderTarget;
    targets.objectIdState = ResourceStates::PixelShaderResource;
    targets.hasValidObjectIdFrame = true;

    DestroyViewportRenderTargets(nullptr, targets);

    EXPECT_TRUE(colorTexture->shutdownCalled);
    EXPECT_TRUE(colorView->shutdownCalled);
    EXPECT_TRUE(depthTexture->shutdownCalled);
    EXPECT_TRUE(depthView->shutdownCalled);
    EXPECT_TRUE(objectIdTexture->shutdownCalled);
    EXPECT_TRUE(objectIdView->shutdownCalled);
    EXPECT_TRUE(objectIdShaderView->shutdownCalled);
    EXPECT_EQ(targets.width, 0u);
    EXPECT_EQ(targets.height, 0u);
    EXPECT_EQ(targets.colorTexture, nullptr);
    EXPECT_EQ(targets.colorView, nullptr);
    EXPECT_EQ(targets.depthTexture, nullptr);
    EXPECT_EQ(targets.depthView, nullptr);
    EXPECT_EQ(targets.objectIdTexture, nullptr);
    EXPECT_EQ(targets.objectIdView, nullptr);
    EXPECT_EQ(targets.objectIdShaderView, nullptr);
    EXPECT_EQ(targets.imguiCpuHandle.ptr, 0u);
    EXPECT_EQ(targets.imguiGpuHandle.ptr, 0u);
    EXPECT_EQ(targets.textureId, ImTextureID{});
    EXPECT_EQ(targets.colorState, ResourceStates::Common);
    EXPECT_EQ(targets.objectIdState, ResourceStates::Common);
    EXPECT_FALSE(targets.hasValidObjectIdFrame);
}

} // namespace